For more details see how Pre Order for Magento 2 extension works.
The extension allows you to market the out of stock or just announced goods. Your customers can pre order or backorder your goods that are temporary unavailable for immediate purchase.
To configure the module, go to admin panel → Stores → Configuration → Amasty Extensions → Pre Order.
Enable Pre Orders - To enable pre orders, set to Yes.
Allow Pre Orders for Products with Zero and Below Zero Qty - Choose whether to allow pre orders for products with zero quantity. If set to “No”, it is possible to pre order products that have quantity set to 1 or higher only. This way you can limit number of products available for pre order.
Disable Pre Order for Items with Qty Above Zero - If set to “Yes”, pre orders will take effect only for products with quantity 0 or lower.
Add to Cart Button Text - Specify the text that will be displayed instead of the Add to Cart button on category and product pages for all pre ordered products.
Default Pre Order Note - You can display the same text with all pre ordered products. It’s possible to use {variables} with product attributes.
Pre-Order Note Output Place - Choose where to display the Pre-Order Note, using selectors. You can specify any valid selector. Also, you can determine several selectors separated by a comma. For example: .stock, .availability. This can be helpful when the output places differ on different pages.
Show Pre-Order Note on Category Pages - Control the display of Pre-Order Notes on the catalog and listing pages.
Pre Order Warning - Create a message to display with order information.
Pre Order Warning in Shopping Cart - This warning is shown only when there is not enough quantity of ordered product. Here the '%1$s' is the product name and the '%2$s' is the pre-ordered product qty.
Use '%1$s' (product name), '%2$s' (pre-ordered product qty) to create your warning message.
Detect Complex Products Which Consist only of Pre-Order Components - When set to Yes, the pre order warning will be displayed before the customer selects any product configuration. The option works for configurable, bundle and grouped products if all their components have pre order status.
Automatically Add Warning to Transactional Emails - When enabled, the Pre-Order Note will be added to transactional emails automatically.
Here's the example of an email with the Pre-Order Note.
To navigate the order grid, go to admin panel → Sales → Orders. You can filter the pre orders by clicking the Pre Order column.
On the order info page all the products ordered in advance will be marked as pre order.
To enable pre order function for a simple product:
In the Advanced Inventory tab, untick Use Config Settings checkbox under Backorders field and select Allow Pre-Orders option from the dropdown.
You can specify custom Pre-Order Cart Button and Pre-Order Note for a simple product. Leave it blank, and the values that you set in the Display Options will be applied.
To activate pre order and customize pre order note & cart button in bulk (for many products at the same time):
To find out what are the simple products of configurable, grouped, or bundle item:
The pre order message you’ve specified for each particular product in the Advanced Inventory tab is displayed on a shopping cart page.
Warning message in the Orders tab of a customer's account.
Pre order note is also displayed at the Checkout in order summary section